Unusual Cause of Respiratory Distress in a Term Neonate.

Respiratory distress is a clinical finding often seen in neonates. Common causes of respiratory distress in this population include respiratory distress syndrome, transient tachypnea of the newborn, infection, aspiration, and cardiac etiologies. We present the case of a neonate who presented with respiratory distress with no identifiable cause on initial workup. The patient was eventually found to have a variant of a genetic mutation that predisposed the infant to this presentation. A term male infant born via spontaneous vaginal delivery was admitted to the pediatric service at 3 weeks of age because of tachypnea. Chest x-ray showed perihilar infiltrates. Septic screen, thyroid function test, sweat test, echocardiogram, intracranial ultrasound, and modified barium swallow were normal. Computed tomography scan of the chest showed ground glass opacities in the upper and lower lobes. Airway evaluation showed no evidence of obstruction or anatomic abnormalities. Bronchoscopy showed no masses or tracheomalacia. Bronchoalveolar lavage was negative for infection. The infant was treated with intravenous antibiotics, steroids, and furosemide but continued to be tachypneic and required supplemental oxygen. Genetic studies were obtained to assess for surfactant deficiencies, and the patient was transferred to another center for a higher level of care. Genetic evaluation was positive for NKX2.1 variance mutation C.190C. The patient's symptoms improved, and he was weaned to room air by 3 months of age. When evaluating a child with unexplained pulmonary disease, clinicians should have a high index of suspicion for interstitial lung disease including surfactant protein mutations.